Roof vent

ABSTRACT

A roof vent for ventilation of a roof, the roof vent adapted to be placed on the pitch of the roof, not the ridgeline. The roof vent has a flat or tabular floor and a base attached to the floor. The floor includes a throat member having vertical walls and the base has sloped back lower walls, and upper walls that are non-horizontal and slope back from the lower walls, and finally a horizontal top. The effect of the nonnormal lower walls and the sloped back upper walls, in conjunction with a typically rectangular flat (parallel to the floor) top provides an airfoil shape to the roof vent that assists in the flow of an over the roof vent.

This patent application claims priority from, benefit of, and incorporates herein by reference U.S. Provisional Patent Application Ser. No. 61/492,132, filed Jun. 1, 2011; and Ser. No. 61/593,586, filed Feb. 1, 2012.

FIELD OF THE INVENTION

Roof vents, namely, roof vents with longitudinal ribs, critter guards, and airfoil shaped walls.

BACKGROUND OF THE INVENTION

Roof vents are provided to allow a building, such as a residence, to “breathe.” Depending on the specifications of the construction, buildings must have minimum net-free area to provide gaseous exchange between the air inside the house and air outside the house. This is often done through the use of roof vents.

However, roof vents that provide gaseous communication between the interior of a house, typically an attic, and the area outside the house, typically adjacent the roof, also provide a path where airborne particles, such as rain or debris, may enter the house or building structure. If the air path is open and accessible, even small animals, such as small birds, insects or the like, may be able to get through an unprotected or open vent opening into the attic of a house.

A vent design must have sufficient net-free area, but at the same time, protect the interior of the house from these hazards. Moreover, roof vents, by their very nature, represent an obstruction to the wind and windborne particles. As such, they may bear loads, especially when the wind is high.

SUMMARY OF THE INVENTION

In an exemplary embodiment, Applicants provide a low profile, aerodynamically shaped wind vent which diverts wind and wind-driven rain or debris up and over a airfoil leading edge. The angled, airfoil leading edge is substantially closed, but with an angled louvered area for ventilation, which angled louvered area is angled back with respect to the airfoil leading edge.

In an exemplary embodiment of Applicants' roof vent, an over/under grid work may be provided for louvers, which help de-accelerate the wind and prevent rain from entering an interior region, including the open throat area of the vent. This over/under grid work also helps prevent windborne debris from collecting or clogging the vent interior, or accessing the vented space.

In an exemplary embodiment of Applicants' novel roof vent, a low profile is provided with an upper surface extending typically 6 inches or less from the base, which low profile design reduces wind load on the vent and generates less stress than prior art designs.

In an exemplary embodiment of Applicants' roof vent, a “tortured” path is provided, sinuous in nature, which makes it difficult for wind-driven rain to enter the ventilated space.

Dimensionally, the roof vent may be rectangular shape, shingle length, and will typically blend into, aesthetically, the shingled roof. It may be molded from two pieces of high impact plastic. It may include UV resistant material for longer life and color retention. An embodiment of Applicants' roof vent is 30 inches long and may be in multiples of 6 inches. Any other suitable dimensions are also anticipated. This aids in shingle trimming and aids in side-to-side location of a vent to coincide with the shingle pattern.

A critter guard is provided and may be of a “waffle” design for efficient flow area and for a larger net-free area. Such critter screen or guard will prevent small animals and the like from entering the attic space.

In a vertical embodiment of Applicants' roof vent, the longitudinal axis of the vent is coincident with the pitch of the roof and provides the appearance of a typical skylight. In a horizontal embodiment, the longitudinal axis of the roof vent is perpendicular to the pitch and coincident with the lines of a typical shingled roof.

A roof vent comprising a rectangular cover having a pair of airfoil shaped closed walls and a pair of airfoil shaped, spaced apart partially open walls, having mouth openings, the cover having a deflection skirt having a removed edge, the skirt depending downward from the underside thereof, and a base having a perimeter portion and a floor portion, the floor for defining a vent opening, the vent opening having vertical walls defining a throat and terminating in a critter guard, the critter guard adapted to allow air to flow therethrough, past the deflector skirt and the mouth openings, wherein the throat is within and spaced apart from the removed edge of the skirt.

A roof vent for ventilation of a roof, the roof vent adapted to be placed on the pitch of the roof, not the ridgeline. The roof vent has a flat or tabular floor and a base attached to the floor. The floor includes a throat member having vertical walls and the base has sloped back lower walls, and upper walls that are non-horizontal and slope back from the lower walls, and finally a horizontal top. The effect of the non-normal lower walls and the sloped back upper walls, in conjunction with a typically rectangular flat (parallel to the floor) top provides an airfoil shape to the roof vent that assists in the flow of air over the roof vent. The cover is typically rectangular and the lower walls will typically have a pair of mouth openings therein and a pair of lower walls that are substantially closed. The substantially closed lower walls typically face down and up pitch, and may be either the long side walls or the short side walls on the rectangular embodiment. The upper walls typically include longitudinal ribs configured to prevent precipitation from dripping in the throat.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric partially cutaway view of a vertical embodiment of Applicants' roof vent illustrating the closed and opened sides and the interior structure of the vent.

FIG. 2 is a top plan view of the vertical embodiment of Applicants' roof vent.

FIG. 3 is a side elevational cutaway view of the vertical embodiment through section B-B of FIG. 2 of Applicants' roof vent.

FIG. 4 is a side elevational view of the vertical embodiment of Applicants' roof vent.

FIG. 5 is a cross-sectional elevational view of the vertical embodiment through section A-A of Applicants' roof vent.

FIG. 6 is an isometric view of the vertical embodiment of Applicants' roof vent.

FIG. 7 is an isometric view of a horizontal embodiment of Applicants' roof vent.

FIG. 8 is a cross-sectional cutaway elevational view of Applicants' horizontal roof vent through section B-B of FIG. 9.

FIG. 9 is a top plan view of the horizontal embodiment of Applicants' roof vent.

FIGS. 10 and 10A are a side elevational and cross-sectional view through section A-A of Applicants' horizontal roof vent.

FIG. 11 is an illustration of Applicants' vertical embodiment of the roof vent mounted to a roof inside elevational view, showing deflection of the wind by the airfoil leading edge of the roof vent.

FIG. 11A is a perspective view of the vertical embodiment of the roof vent attached to a shingled roof.

FIG. 12 is a partial detail side elevational view of the leading edge as seen in FIG. 11 and the manner in which it deflects wind.

FIG. 13 is a perspective view of the horizontal embodiment of the roof vent attached to a singled roof.

FIG. 14 is a vertical version of a preferred embodiment 10 c in perspective view with a partial cutaway of the top wall.

FIGS. 15 and 16 is a horizontal version of the preferred embodiment of FIGS. 14-21 in top elevational view and side elevational cutaway views, respectively, showing the manner in which the upstanding vertical slats of this embodiment trend parallel to the side walls.

FIG. 17 is a detail view of the staggered horizontal ribs of the grid work above the lower walls of the cover.

FIGS. 18 and 19 are front elevational and front cutaway views of the horizontal version of the preferred embodiment of Applicants' present invention, with FIG. 17 a detailed view of the manner in which the slats “overlap” one another.

FIGS. 20 and 21 are perspective views of a horizontal version of Applicants' preferred embodiment.

FIG. 22 is a cross-section of the roof vent on a steep pitched roof illustrating a vertical drop line gap.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In FIGS. 1-6, a vertical embodiment of Applicants' roof vent 10 is illustrated. Roof vent 10 a is comprised of a generally tabular base 12, which base rigidly engages a cover 14. Base 12 is seen to have a perimeter portion 16 and a floor portion 18. Floor portion 18 defines a vent opening 20. A critter guard 22 is provided to impede access of small animals to the vent opening 20. Raised side walls 24 with an upper edge 24 a are set on the inner edges of floor portion 18 which define vent opening 20. Vent opening 20, in conjunction with raised side walls 24, defines a throat T, typically rectangular, through which an attic or other space is ventilated, by placement of the vent opening over the roof opening.

Vent opening 20 is generally rectangular in a preferred embodiment as is perimeter portion 16, which extends beyond the cover. That is to say, perimeter portion 16 is that area beyond the cover and floor portion 18 is substantially beneath the cover.

Critter guard 22 is seen to have a vented ribbed “waffle” type top wall 26 engaging upper edge 24 a of the raised side walls 24. Vented “waffle” top wall 26 is comprised of multiple V-shaped members 30. Each V-shape member 30 is seen to have depending side walls 30 a/30 b. The multiple side walls 30 a/30 b, which make up the multiple V members 30, have spaced apart parallel bars 32. These may be spaced, for example, with gaps of about ¼ inch between them for allowing the throat T to breathe and air to pass through as generated by the pressure differences between the inside of the structure and the outside thereof. Presenting a top wall 26 waffled as illustrated provides for a larger air path than a planar structure with the same bars and gaps that is tabular across the upper edge 24 a.

Cross braces 28 (see FIG. 1) are seen to cross from one raised wall 24 to an opposing raised wall and may support upper and lower long beams 34/36 so as to give some rigidity to critter guard 22. Moreover, standing support 29 projecting upward from the floor portion 18 of the base may, in one embodiment, toolessly, fasten or snap, to engage depending support 31, which depends downward from the underside of cover 14 as illustrated in FIGS. 1 and 3. This provides a vertical spaced apart support of a top wall 48 of cover 14. There may be multiple sets of elements 29/31 located spaced apart between the floor 18 and the underside of the cover.

Turning now to cover 14, it is seen that cover 14 may be comprised of side walls 44, which depend upward from base 12 and are canted at a non-normal or non-perpendicular angle typically in the range of about 5 to about 20 degrees so they may deflect wind that impinges on them. Furthermore, and with reference to FIG. 3, vented walls 42 are seen to be provided with a grill-like or louvered structure to allow air to communicate between the cover and the throat as set forth in more detail below. The vented walls 42 are seen to be canted back from perpendicular at angles greater than the side wall, but less than 90 degrees, typically in the range of about 25-75 degrees. Last, a generally flat laying top wall 48 is provided to complete the airfoil effect, as seen in FIGS. 11 and 12, for example.

As can be seen with reference to FIGS. 3 and 4, and with reference to the vertical embodiment 10 a, it is seen that side walls 44 a/44 b are substantially closed, yet side walls 44 c/44 d are at least partially open and have walls defining mouth openings 52/54, as seen in FIGS. 2 and 6. The angular relationship between side walls 44 a/44 b and the adjacent vented walls 42 and top wall 48 may be seen with reference to FIG. 3 to be, in side view, airfoil shaped. Side wall 44 a may be, in a vertical embodiment 10 a, placed on the roof as seen in FIG. 11, and is typically positioned so that it faces “down pitch.” Therefore, winds driven “up pitch” will impinge on side wall 44 a (which is substantially closed) and, given the canted back disposition of side wall 44 a and vented walls 42, along with a horizontal (with respect to the base) top wall 48 will be seen to deflect such air as illustrated by the arrows in FIGS. 11 and 12. That is to say, the leading edge facing the down pitch position in a vertically oriented embodiment of Applicants' vent roof 10 a may be seen to provide a substantially closed leading airfoil edge, here side wall 44 a, to the windward side of the roof. Venting, through mouth openings 52/54, typically does not face the prevailing wind.

Moreover, it is seen with reference to the skirted embodiment of FIGS. 1-13, that top wall 48 has an inner skirt 50 depending vertically down from the inside surface of the top wall 48 as best illustrated in FIGS. 3 and 5. Skirt 50 defines a rectangular downward projection whose removed edge 50 a is spaced apart laterally from the upper edge 24 a of side walls 24 creating a circuitous path or torturous, sinuous path for air escaping from mouths 52/54 (see arrows showing vent flow in FIGS. 3 and 8. It is seen that inner skirt 50 will help prevent raindrops carried by a wind flow coming in through vents of vented walls 42 to the vent opening 20.

In addition to assisting with the creation of a circuitous path, skirt 50 acts to block windblown debris, rain or the like that enters the interior of the base from the vent opening. Air may flow through either the mouth or through vented walls 42, but debris is either deflected over the roof vent by the airfoil action or, if it enters the interior, is deflected by skirt 50. It is seen that the upper edge 24 a of side walls 24 and the lower edge 50 a of skirt 50 are positionally space apart, but in addition, removed or lower edge 50 a is typically lower or closer to base 12 than upper edge 24 a. Moreover, both the side walls and the skirt are rectangular shaped, with the rectangular skirt being larger than the rectangle defined by the four skirt walls 24 a and, thus, regardless of the direction of the wind and windborne particles, there is a physical barrier that will likely catch most of the debris or rain.

Turning to FIG. 8, and the illustration of airflow through the horizontal version of Applicants' roof vent 10 b, a number of stages can be seen to define the circuitous or tortuous route of air ventilating the vent opening 20. For sake of illustration, we will look at air moving from inside the home or other structure to the outside. First, air passing through vent opening 20 is seen to take a generally vertical or upward route with respect to horizontal, as seen in FIG. 8. This is the result of the constriction of the four side walls 24 a. In its pathway to the mouth opening 56, air will flow between the underside of the top 48 and upper edge 24 a and then be forced, by skirt 50 and the position of lower edge 50 a, to depend downward and at least somewhat parallel to base 12 for exiting, typically through the mouth or up through vented walls 42 as seen in FIG. 8.

In FIG. 11, there is illustrated a vertical mount of the vertical embodiment 10 a of the roof vent. In FIG. 13 is illustrated the relationship of the horizontal roof vent to surrounding shingles, and a means 58, such as nails, for mounting the roof vent 10 to the roof. In FIG. 13, the horizontal embodiment 10 b of Applicants' roof vent 10 is seen to engage shingles so as to lay in a position with its longitudinal axis perpendicular to the pitch of the roof.

Thus, as seen how Applicants have provided for a roof vent in one embodiment with a tortuous airflow, with an aerodynamic shape that discourages entry of debris into an interior space of the roof vent by deflecting debris from entering the vent, while providing a critter guard and other favorable features in an efficient, low profile roof vent that may be mounted horizontally or vertically to the roof as indicated.

FIGS. 14-21 illustrate an alternate preferred embodiment 10C of Applicants' present invention. Alternate preferred embodiment 10C in a vertical embodiment (see FIG. 14) has two substantially closed airfoil side walls 44 a/44 b and two partially opened side walls 44 c/44 d, which partially opened side walls 44 c/44 d are opposite one another and either wall 44 a or 44 b is oriented down pitch (see FIG. 11A). On the other hand, Applicants provide an alternate preferred embodiment 10 c in a horizontal embodiment (see FIG. 15), in which substantially closed airfoil side walls 44 a/44 b are oriented, at least one of them, down pitch (see FIG. 13). However, in Applicants' alternate preferred embodiment, whether vertical or horizontal, it is noted that vented side walls 42 (on all four walls 44 a/44 b/44 c/44 d) have a grid portion with multiple staggered horizontally trending ribs/slats 45 a/45 b/45 c/45 d (see FIG. 17). Moreover, the length L (see FIG. 17) of each slat is such that, when windborne rain is driven substantially horizontal, it will strike the surface of one of the multiple horizontal rib or slats 45 a/45 b/45 c/45 d. That is, there is no gap (viewed horizontally) to the vents interior, for rain being carried in the direction of the arrows in FIG. 17. As further explanation, in the side elevational view of FIG. 18, the ribs/slats are staggered or overlap as they trend upward 45 a/45 b/45 c/45 d, so that in viewing the grid work “straight on,” no gaps are apparent. But the view, top elevational looking down, as seen in FIG. 15, for example, clearly shows the gaps for generating airflow. Moreover, the raised side walls 24 defining the throat T are well inside the gap of the uppermost slat 45 d, so water drainoff and down into the interior of the vent avoids the throat and the attic interior. That is to say, it is difficult, with the staggering and the length L as indicated, for debris or rain to freely enter the throat and attic interior of the vent through vented walls 42.

Moreover, it is seen that the alternate preferred embodiment 10C illustrated in FIGS. 14-21 (both vertical and horizontal versions) do not use a skirt as illustrated in the previous embodiments set forth in FIGS. 1-13. All other features are substantially the same. It is noted, however, that in the horizontal version, the smaller substantially at least partially open side walls 44 c/44 d (see, for example, FIG. 15), are placed to allow a maximum air to flow through. The airfoil side walls 44 a/44 b may have small openings 47 a/47 b as seen in FIG. 15, which small openings provide sufficient net-free airflow to allow proper breathing. That is to say, in the horizontal version, small openings 47 a/47 b are provided to meet a minimum net-free airflow, but may not be needed in the vertical version illustrated in FIG. 14, because in the vertical version, there is sufficient area in the “long” side walls that a sufficient net-free area is achieved. In other words, in the horizontal embodiment wherein the open side walls are on the short side, additional openings need to be provided in the airfoil side walls, as indicated with openings 47 a/47 b. Although the openings are sized to realize a net free area minimum, the various embodiments may have any suitable sizes.

In any embodiments, the substantially airfoil side walls 44 a/44 b, which are typically closed or substantially closed, there may be drain holes 49 a, as seen in FIG. 14, so that when the side walls are down pitch and water collects at the lowest point down pitch, it may drain.

Moreover, it is seen with reference to FIGS. 16 and 19 that inner perimeter 51 of the inner, upper edge of the grid work is outside of the inner perimeter of the upper edge of 24 a. By such careful placement, debris or windborne rain or the like that strikes the outer or outward facing surfaces of the horizontally aligned slats 45 a/45 b/45 c/45 d, which are horizontally disposed, but have a vertical length allowing rain and the like to drop down into the inside of the cover, but not drip into the inside of the throat.

The critter guard 22 and, specifically, the critter guard with the waffle shape and cross-section as seen in FIG. 19, for example, is a novel feature that may be used with any roof vent or any roof vent with a throat T regardless of any of the other features on the roof vent. Moreover, the depending skirt 50 as seen in FIG. 3, for example, is a feature that may be used with or without the other features disclosed herein. In a preferred embodiment, there is no skirt used with ribs that run longitudinally as seen, for example, in FIG. 14, rather than the vertical slats or ribs as seen, for example, in FIG. 1. Indeed, in the preferred embodiment, longitudinal ribs (usually two or more, preferably four) preclude the need for a skirt, although a skirt may be used in conjunction with longitudinal or vertical ribs.

The lower walls of the roof vent may make an angle with respect to an axis perpendicular to the floor of between about 9°-15° and, in one preferred embodiment, about 12°. The upper walls, which typically include the vents or grid work, in a preferred embodiment have longitudinal ribs, and make an angle of between about 55°-65° with perpendicular axis, and in one embodiment about 58°.

In a preferred embodiment, the maximum height of the top wall of the cover above the floor is 6 inches. That is to say, the top wall in a preferred embodiment is typically parallel to the floor and a maximum of 6 inches above the floor and, in a preferred embodiment, about 5 inches.

The included angles on the waffle shape critter guard 22 are preferably between about 45°-135° and, in one preferred embodiment, about 75°. Typically, Applicants' cover is rectangular as seen in top elevational view, for example, in FIG. 7, and has a length L and width W such that the aspect ratio (L/W) is between about 1.2-2.2 for one preferred embodiment designed for use with regular shingles. Architectural shingles with different dimensions may require different lengths and widths, but would still typically include a rectangular cover and a floor that is rectangular.

Turning to FIG. 22, a vertical drop line 60 is seen to generate a positive gap 62 or space outward from the upper lip 24 a of the throat T. Typically, the maximum pitch will be a 16/12 (16 up, 12 out), such as is illustrated in FIG. 22. At this maximum pitch, it is seen that a vertical drop line from the upper edge of the grid work in the embodiment with the longitudinal ribs will provide a positive gap 62 away from the upper lip 24 a of the throat T. This is so that rainwater dropping down vertically, from inner perimeter 51 that will be closest to the throat, does not fall into the throat. If a positive gap is left, then even if there is some momentum to water drops as they hang off the lower edge of the upper wall of the grid and do not fall straight down but fall at an angle as indicated, a positive gap will tend to prevent the water droplets, even with some momentum that carries them toward the throat, from entering the throat.

Applicants provide for a novel waffle shape critter guard that may be used alone or in combination with the rib configuration and/or the airfoil shaped walls. Indeed, the rib configuration and the airfoil shaped walls may stand alone without the other features disclosed herein.

Although the invention has been described with reference to a specific embodiment, this description is not meant to be construed in a limiting sense. On the contrary, various modifications of the disclosed embodiments will become apparent to those skilled in the art upon reference to the description of the invention. It is therefore contemplated that the appended claims will cover such modifications, alternatives, and equivalents that fall within the true spirit and scope of the invention. 

1. A roof vent comprising: a cover having walls, including lower walls, each of the lower walls having a longitudinal axis, the lower walls comprising a pair of non-normal, opposed, substantially closed walls and a pair of non-normal, opposed, spaced apart walls, having mouth openings; wherein the cover walls of the cover include a non-horizontal upper wall angled back from each lower wall, each upper wall including a grid work portion, the grid work portion with a multiplicity of ribs arranged with their longitudinal axes parallel to the longitudinal axis of the lower wall; and a base for engaging the lower walls, the base having a perimeter portion and a floor portion, the floor portion inside the junction between the lower walls and the base, the floor portion for defining, in part, a vent opening, the vent opening having generally vertical walls defining a throat terminating at an upper lip.
 2. The roof vent of claim 1, wherein the cover includes a top wall, the top wall substantially parallel to the floor.
 3. The roof vent of claim 1, wherein the lower walls make an angle of between about 9 and 15 degrees with an axis perpendicular with respect to the floor and wherein the upper walls make an angle of between about 55 and 65 degrees with respect to an axis perpendicular to the floor.
 4. The roof vent of claim 1, wherein the cover includes a closed top wall, the top wall substantially parallel to the floor and wherein the upper walls include a closed portion above the grid work portion.
 5. The roof vent of claim 1, wherein the grid work portion includes support struts running generally perpendicular to the ribs.
 6. The roof vent of claim 1, wherein the ribs are generally parallelogram shaped, having a top wall, a pair of spaced apart side walls, and a bottom wall.
 7. The roof vent of claim 1, wherein the ribs are staggered such that the top wall of the lower rib is above the bottom wall of the adjacent, higher rib.
 8. The roof vent of claim 1, wherein the ribs are generally tabular, having a top wall, a pair of spaced apart side walls, and a bottom wall and wherein the ribs are staggered such that the top wall of the lower rib is above the bottom wall of the adjacent, higher rib.
 9. The roof vent of claim 1, wherein the throat is within and spaced apart from a removed edge of the grid work portion such that precipitation entering the grid work portion will not enter the throat.
 10. The roof vent of claim 1, wherein the lower walls having mouth openings are shorter than the substantially closed lower walls.
 11. The roof vent of claim 1, wherein the lower walls having mouth openings are longer than the substantially closed lower walls.
 12. The roof vent of claim 1, wherein the cover and base are rectangular.
 13. A roof vent comprising: a rectangular cover having walls, including lower walls, each of the lower walls having a longitudinal axis, the lower walls comprising a pair of airfoil shaped, opposed, substantially closed walls and a pair of airfoil shaped, opposed, spaced apart walls, having mouth openings; wherein the cover walls of the rectangular cover include an upper wall angled back from each lower wall, each upper wall including a grid work portion, the grid work portion with a multiplicity of upstanding ribs arranged with their longitudinal axes parallel to the longitudinal axis of the lower wall; and a base for engaging the lower walls, the base having a perimeter portion and a floor portion, the floor portion inside the junction between the lower walls and the base, the floor portion for defining, in part, a vent opening, the vent opening having generally vertical walls defining a throat and terminating in a critter guard, the critter guard adapted to allow air to flow therethrough; wherein the throat is within and spaced apart from a removed edge of the grid work portion such that precipitation entering the grid work portion will not enter the throat; wherein the ribs are generally parallelogram shaped, having a top wall, a pair of spaced apart side walls, and a bottom wall and wherein the ribs are staggered such that the top wall of the lower rib is above the bottom wall of the adjacent, higher rib; and wherein the cover includes a top wall, the top wall substantially parallel to the floor; wherein the lower walls make an angle of between about 9 and 15 degrees with an axis perpendicular with respect to the floor and wherein the upper walls make an angle of between about 55 and 65 degrees with respect to an axis perpendicular to the floor; wherein the cover includes a closed top wall, the top wall substantially parallel to the floor and wherein the upper walls include a closed portion above the grid work portion; and wherein the grid work portion includes support struts running generally perpendicular to the ribs.
 14. A roof vent comprising: a cover having walls, including lower walls, some substantially closed and some having mouth openings; and a base for engaging the cover walls, the base having a perimeter portion and a floor portion, the floor portion inside the junction between the cover walls and the base, the floor portion for defining, in part, a vent opening, the vent opening having generally vertical walls defining a throat terminating in a critter guard, the critter guard having waffled walls adapted to allow air to flow therethrough; the throat is within and spaced apart from a removed edge of the grid work portion such that precipitation entering the grid work portion will not enter the throat.
 15. The roof vent of claim 14, wherein the cover is rectangular and wherein the lower walls include a pair that has mouth openings and a pair that is substantially closed.
 16. The roof vent of claim 14, wherein the cover includes a top wall, the top wall substantially parallel to the floor.
 17. The roof vent of claim 14, wherein the lower walls of the cover make an angle of between about 9 and 15 degrees with an axis perpendicular with respect to the floor and further including upper walls which make an angle of between about 55 and 65 degrees with respect to an axis perpendicular to the floor.
 18. The roof vent of claim 14, wherein the cover further includes walls defining a grid work portion having ribs and support struts running generally perpendicular to the ribs.
 19. A roof vent comprising: a rectangular cover having walls, including lower walls, each of the lower walls having a longitudinal axis, the lower walls comprising a pair of airfoil shaped, opposed, substantially closed walls and a pair of airfoil shaped, opposed, spaced apart walls, having mouth openings; wherein the cover walls of the rectangular cover include a non-horizontal upper wall angled back from each lower wall, each upper wall including a grid work portion, the grid work portion with a multiplicity of ribs; and a base for engaging the lower walls, the base having a perimeter portion and a floor portion, the floor portion inside the junction between the lower walls and the base, the floor portion for defining, in part, a vent opening, the vent opening having generally vertical walls defining a throat; wherein the cover includes a top wall, the top wall substantially parallel to the floor.
 20. The roof vent of claim 19, wherein the lower walls make an angle of between about 9 and 15 degrees with an axis perpendicular with respect to the floor and wherein the upper walls make an angle of between about 55 and 65 degrees with respect to an axis perpendicular to the floor.
 21. The roof vent of claim 19, wherein the cover includes a closed top wall, the top wall substantially parallel to the floor and wherein the upper walls include a closed portion above the grid work portion.
 22. The roof vent of claim 19, wherein the grid work portion includes support struts running generally perpendicular to the ribs.
 23. The roof vent of claim 19, wherein the cover includes a top wall, the top wall substantially parallel to the floor; wherein the lower walls make an angle of between about 9 and 15 degrees with an axis perpendicular with respect to the floor and wherein the upper walls make an angle of between about 55 and 65 degrees with respect to an axis perpendicular to the floor; wherein the cover includes a closed top wall, the top wall substantially parallel to the floor and wherein the upper walls include a closed portion above the grid work portion; and wherein the grid work portion includes support struts running generally perpendicular to the ribs.
 24. A static structure comprising: a pitched roof; and a roof vent comprising a cover having walls, including lower walls, each of the lower walls having a longitudinal axis, the lower walls comprising a pair of non-normal, opposed, substantially closed walls and a pair of non-normal, opposed, spaced apart walls, having mouth openings; wherein the cover walls of the cover include a non-horizontal upper wall angled back from each lower wall, each upper wall including a grid work portion, the grid work portion with a multiplicity of ribs; and a base for engaging the lower walls, the base having a perimeter portion and a floor portion, the floor portion inside the junction between the lower walls and the base, the floor portion for defining, in part, a vent opening, the vent opening having generally vertical walls defining a throat terminating at an upper lip; wherein the roof vent engages the pitched roof such that the pair of opposed, substantially closed walls are oriented up and down pitch. 